It is often desirable to sense the angular position of a rotating part. Numerous kinds of rotation sensors have been developed over the years. One type of rotation sensor is a capacitive sensor, where a capacitance varies according to angular position. Rotary sensors known in the art are lacking in resolution and generally have an oversized form factor, making them impractical for applications requiring maximum signal production for a limited sensing area, in addition to having differential cancellation of offset bias and gain terms to reject noise caused by motion not in the direction of rotation the sensor.
What is needed is a rotary position sensor with high resolution and a reduced form factor that is able to operate for long periods of time, while having a reduced cost of fabrication.